Access floor systems or elevated floor structures have gained much popularity with the introduction of computer systems. These elevated floor structures comprise of floors constructed by arranging generally rectangular floor panels in side by side relation in a rectangular array. More particularly, the floor panels generally comprise a bottom surface spaced from a top surface so as to present four sides thereof. In one arrangement the top surface extends beyond the bottom surface so as to present a lip along each of the four sides which is adapted to being supported by stringers supported at the ends thereof by a plurality of pedestals defining a grid pattern. The floor panels can be individually removed for servicing.
Generally speaking, the access floor panels are required to have a generally low resistance or in other words a high conductivity between the top of the floor panel and the bottom of a pedestal which is generally supported by a building ground. In some applications the access floor panel is required to have an electrical resistance of less than 10 ohms when measured between the top of the bare panel i.e. the metallic surface and the bottom of the pedestal where it can be connected to a building ground. In other applications, the resistance must fall within the range of one to less than 10 ohms.
In order to accomplish such high conductivity the solutions ranging to date and the prior art include having a spring clip which are mounted to the stringer to make electrical contact to the floor panel. However, the floor panel is generally painted, and the paint is a poor conductor thus increasing the resistance. In other applications, brass strips are laminated between the laminate top of the top surface of the floor panel and the bare panel. Such remedies are sometimes ineffective as the panel paint must be scratched and the brass strips must touch the stringers.
Furthermore, other arrangements are shown in U.S. Pat. No. 5,888,104 which relates to an electrical grounding connector comprising a U-bolt, a upper clamp part and a lower clamp part. The upper clamp part is connected to the U-bolt, to clamp a floor pedestal there between.
Furthermore U.S. Pat. No. 4,976,627 illustrates an electrical connector for mechanically and electrically connecting conductors.
Furthermore U.S. Pat. No. 4,780,571 relates to a combined floor pedestal and floor outlets which include a base drum and a support drum and are interconnected by an adjustment sleeve member which is sleeved around and threadedly connected to the base drum and support drum. The assembly is convenient for making height adjustments as well as electrical connection.
It is an object of this invention to provide an improved device where electrically grounding an access floor panel to a floor panel support. It is the further object of this invention to provide an improved method of grounding a floor panel in a grid defined by a plurality of stringers supported by a plurality of pedestals.
It is an aspect of this invention to provide a device for electrically grounding an access floor panel to a floor panel support comprising a clip fastened to the floor panel, the clip compressible against the support when the floor panel is placed against the support.
It is another aspect of this invention to provide a floor panel for a raised access floor defined by a plurality of floor panels each supported by a grid of horizontally disposed stringers, the stringers are supported at the ends thereof by a plurality of pedestals respectively, the floor panel having a rectangular bottom surface and a rectangular top surface spaced from said bottom surface by four sides thereof, said top surface extending beyond said bottom surface to define a lip along four sides thereof, each said lip adapted to be supported by one of said stringers, where one of said sides includes a recess adapted to receive a spring clip adapted to spring against said stringer when said floor panel is supported by said stringer of said grid.
It is yet another aspect of this invention to provide a method of grounding a floor panel in a grid defined by a plurality of stringers supported by a plurality of pedestals comprising the steps of; electrically fastening a deformable metal clip to one side of said floor panel; placing said floor panel into said grid so as to support said floor panel on said stringers compressing said spring against said stringer so as to make electrical contact thereto.
These and other objects and features of the invention shall be described in relation to the following drawings.